"We were on a balcony that overlooks the ocean. It was just beautiful," he told Hello! magazine. "She said yes! And then she smiled for the rest of the night!"

He continued: "I knew she was 'The One' pretty early on."

Osbourne said: "I've never felt this close to another human being, ever. People say we're co-dependent but we just want to be together all the time."

The couple first met at the 2011 wedding of Kate Moss and Jamie Hince, who is Alison Mosshart's bandmate.

Kelly Osbourne spoke of her partner's move from New York to Los Angeles to be with her, saying: "Matthew made the biggest sacrifice anyone's ever made for me, to move away from everything that he knew to be with me in LA.

"Long-distance relationships often don't work out. We'd dated for a year and knew we wanted to be together. Matthew has broken down every one of my walls. There's nothing I wouldn't do in front of him."

She added that her diamond engagement ring was designed to look like her father Ozzy Osbourne's famous jewelry.

"I designed it to look like an earring that my father wore," she said. "I used to hold my finger up to his ear when I was little and say, 'I want a ring like that'. Now I have one!"